10. Answer: 42° and 138° Steps: First find value of x by adding both equations and setting them equal to 180°: 3x + 12x - 30 = 180 15x - 30 = 180 15x = 210 x = 14
Next, put value of x into equations to find the angle: 3x 3(14) 42°
12x - 30 12(14) - 30 168 - 30 138°
11. Answer: 28° Steps: Complementary angles add up to 90°, so subtract 62° from 90° to find its complementary angle. 90 - 62 = 28
